New process could save the company a ton of dough, and neodymium.
There are still a few hangups with electric vehicles. They still cost more than the equivalent gasoline counterparts. They still produce range anxiety for most customers. And we still get a lot of our electricity from fossil fuels. All of that is in addition to the problem of sourcing and recycling rare earth metals. But Nissan has an answer for that, at least the recycling part. GM already has an idea to reduce the impact of mining for the metals.
The Japanese company partnered with Waseda University and said it has started testing a jointly developed recycling process that recovers those rare earth elements from magnets in the motors. Nissan says the testing should bring practical applications to bear by the mid-2020s. That bodes well for vehicles like the Ariya EV and its new Kei car.
Most motors use neodymium magnets, which contain neodymium and dysprosium, Nissan says. To use the supply more effectively, Nissan is trying to reduce the amount it needs and is recycling old magnets in motors that do not meet its production standards. The problem is that multiple steps, including manual disassembly are required for the current process.
In March of last year, the collaboration developed a "pyrometallurgy process that does not require motor disassembly." For the chemistry nerds, here's the process, straight from Nissan.
First a carburizing material and pig iron are added to the motor, which is then heated to at least 1,400-degrees Celsius and begins to melt. Then iron oxide is added to oxidize the rare earth elements in the molten mixture. After that, a small amount of borate-based flux, which is capable of dissolving rare-earth oxides even at low temperatures, is added to the mix. It separates into two liquid layers, with the molten oxide layer (slag) that contains the REEs floating to the top, and the higher density iron-carbon (Fe-C) alloy layer sinking to the bottom. Finally, the elements are then recovered from the slag.
Nissan says that this process can recover 98% of the motors' rare earth elements, while reducing the work time by 50% compared to the current method. The company will continue testing until the process is perfected, sometime this decade.
The collaboration is part of Nissan's Green Program 2022, which is trying to address four issues: climate change, resource dependency, air quality and water scarcity. This new process will help with at least three of those, and maybe all four. Nissan recently sold its share in Daimler aiming to use the profits to invest more fully in green initiatives like this.